CVE-2021-47316 (GCVE-0-2021-47316)

Vulnerability from cvelistv5 – Published: 2024-05-21 14:35 – Updated: 2026-08-05 08:47
VLAI
Title
nfsd: fix NULL dereference in nfs3svc_encode_getaclres
Summary
In the Linux kernel, the following vulnerability has been resolved: nfsd: fix NULL dereference in nfs3svc_encode_getaclres In error cases the dentry may be NULL. Before 20798dfe249a, the encoder also checked dentry and d_really_is_positive(dentry), but that looks like overkill to me--zero status should be enough to guarantee a positive dentry. This isn't the first time we've seen an error-case NULL dereference hidden in the initialization of a local variable in an xdr encoder. But I went back through the other recent rewrites and didn't spot any similar bugs.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-05-21 18:45 UTC
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: d505e66191072748620fc0af038cea4e4da0e3cd , < e79057d15d96ef19de4de6d7e479bae3d58a2a8d (git)
Affected: 20798dfe249a01ad1b12eec7dbc572db5003244a , < 650e6f383a6eb40f7c0a010982a74ab4b6893870 (git)
Affected: 20798dfe249a01ad1b12eec7dbc572db5003244a , < ab1016d39cc052064e32f25ad18ef8767a0ee3b8 (git)
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Linux Linux Affected: 5.13
Unaffected: 0 , < 5.13 (semver)
Unaffected: 5.13.4 , ≤ 5.13.* (semver)
Unaffected: 5.14 , ≤ * (original_commit_for_fix)
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Siemens RUGGEDCOM RST2428P Unaffected: 0 , < * (custom)
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Siemens SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family Unaffected: 0 , < * (custom)
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Siemens SCALANCE XCM-/XRM-/XCH-/XRH-300 family Unaffected: 0 , < * (custom)
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Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem Affected: 0 , < * (custom)
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Show details on NVD website
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.